The use of organosilanes as adhesion promoters and as modifiers for adhesives to improve the bond strength of the adhesive to substrates is well known. For example, organosilanes are used to modify epoxy resin based adhesives to provide improved adhesion to steel, concrete, aluminum, etc. Organosilanes are also used to modify mineral-filled phenolic, urethane, polyester, furan and other thermosetting resins to improve adhesion between the mineral filler and resin matrix, thereby improving the overall strength of the composite. Likewise, the use of organosilanes to treat or size glass fibers and flakes to thereby provide improved adhesion to various organic resin binder systems in composites is also well known.
Certain adhesive/adherend system applications call for a high degree of bond strength that the above-described systems comprising either organosilane-modified adhesives or organosilane-modified adherends are not capable of providing. It is, therefore, desirable that an adhesive/adherend system be developed that is capable of providing an enhanced degree of bond strength when compared to adhesive/adherend systems that either lack organosilane modification altogether or that comprise a single organosilane-modified component, i.e., an organosilane-modified adhesive or an organosilane-modified adherend alone. It is desired that such an adhesive/adherend system be capable of curing at ambient temperature, develop bond strength very quickly, have a good degree of chemical resistance, and be suitable for continuous use at temperatures up to approximately 250.degree. F.